Electronic Device Used In A Health Care Setting

ABSTRACT

An electronic device for use in a health care setting has a rigid enclosure assembly formed by a rigid shell and a rigid printed circuit board carrying circuitry for operating the device. A switch dome layer and an overlay are independently attached to the device but not to each other, whereby the overlay may be removed without disturbing the dome layer and a better tactile response is achieved.

FIELD OF THE INVENTION

The present invention is generally directed to an electronic device thatis used in a health care setting, such as a hospital, nursing home,clinic, or similar environment. By way of example, the electronic devicemay be a hand-held pillow speaker kept at a patient's bedside forremotely controlling a television, room lights, or other electronicitems in the room, and for communicating with nursing staff or otherpersonnel.

BACKGROUND OF THE INVENTION

Many electronic control and/or or communication devices, including priorart pillow speakers found in hospital rooms, have a rigid enclosureassembly for physical protection and electrical isolation. Formanufacturability, it is commonplace to create the rigid enclosureassembly by providing two complementary rigid shells, and screwing,clipping or gluing the shells together with a printed circuit board(PCB) and any other electronic components inside the rigid enclosureassembly.

Where the electronic device has user control buttons, these aretypically incorporated into the device by a switch membrane mounted onone of the shells. A typical switch membrane either comprises the entireswitch assembly and a wire harness to drive the signals to the PCB, orit includes the metal domes within its confines and adheres the domes tothe PCB to create a normally open switch.

Electronic devices used in health care settings are used on a dailybasis, and they are cleaned and disinfected often to prevent the spreadof germs. They must be reliable for patient safety reasons.Consequently, they require service and repair more frequently thanelectronic devices used under less demanding circumstances.

Electronic devices formed according to the prior art are susceptible todamage not only from normal use, but also from liquid cleaning anddisinfecting agents. Oftentimes, it is the switch membrane that isdamaged, and the entire switch membrane must be removed and replaced,even though an outer graphic overlay of the switch membrane or metalswitch domes of the switch membrane may be in perfect condition.

Switch membranes of the prior art, wherein the switch domes are attachedto the overlay material, give the electronic device a tactileperformance that is less than ideal due to the resistance to movementintroduced by the overlay material.

What is needed is an improved electronic device assembly that is easierand less expensive to manufacture, allows for more efficient and lesswasteful servicing, and responds better from a tactile standpoint to auser's pushbutton touches.

SUMMARY OF THE INVENTION

In a first aspect of the invention, an electronic device for use in ahealth care setting generally comprises a rigid shell defining aninterior space and an opening communicating with the interior space, anda rigid PCB fixed to the shell to cover the opening. The rigid PCBincludes electronic circuitry for operation of the device. The shell andPCB cooperate with one another to form a rigid enclosure assembly forthe electronic device, thereby avoiding the need for a two-piece shellto enclose a separate PCB.

In a second aspect of the invention, an electronic device for use in ahealth care setting is improved by providing a physically separate domelayer and overlay. The dome layer may be fixed to an outward surface ofthe PCB and include a nonconductive sheet and a switch dome attached tothe nonconductive sheet, wherein the switch dome is operable to close aswitch trace on the PCB. The overlay may be arranged adjacent to thedome layer and fixed to a housing shell containing the PCB and/or to theoutward surface of the printed circuit board, but the overlay isunattached to the dome layer. The overlay includes a switch graphic at alocation corresponding to the switch dome.

The present invention extends to methods of making and servicingelectronic devices embodying one or both of the aspects summarizedabove.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is an exploded perspective view of an electronic device formed inaccordance with an embodiment of the present invention;

FIG. 2 is a top plan view showing a printed circuit board, a dome layer,and an overlay of the electronic device in greater detail;

FIG. 3 is a top plan view of the dome layer adhered to the printedcircuit board;

FIG. 4 is a plan view of an internal surface of overlay; and

FIG. 5 is a top plan view of the overlay adhered to the printed circuitboard overtop the dome layer.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows, in exploded view, a pillow speaker 10 formed in accordancewith an embodiment of the present invention. Pillow speaker 10 is anelectronic device for use in a health care setting, such as a hospital,nursing home, clinic, or similar environment. While the presentinvention is described with respect to a pillow speaker, it will beunderstood that other types of electronic devices used in health caresettings may be constructed as taught herein. Examples of other types ofelectronic devices to which the present invention may be appliedinclude, without limitation, handheld pendants, bed rails, wall plates,and call cords where a user interface is required.

Pillow speaker 10 generally comprises a rigid shell 12, a rigid PCB 14,a dome layer 16, and an overlay 18. Shell 12 defines an interior space15 and an opening 30 communicating with the interior space. Shell 12 mayinclude a plurality of fastener receptacles 20, a cord passageway 26through which wires may pass to reach interior space 15, a speaker mount28 for receiving an audio speaker (not shown), a support surface 32 forsupporting PCB 14, an inner surface 33 generally orthogonal to supportsurface 32 in the region of the support surface, and a rim surface 34around opening 30. Shell 12 may also include a retainer tab 35protruding from rim surface 34 overtop support surface 32.

In the embodiment shown in FIG. 1, shell 12 is manufactured from a firstshell portion 12A and a second shell portion 12B. The first and secondshell portions 12A, 12B may each be molded of plastic, and then attachedto one another to form rigid shell 12. It is advantageous that the shellbe free of small openings through which moisture may penetrate. Shellportions 12A and 12B may be ultrasonically welded together, as evidencedby weld seam 13, to form rigid shell 12. Alternatively, a moisturesealing adhesive may be used to bond the shell portions together. Rigidshell 12 may also be formed in unitary fashion as a single piece ofmolded plastic.

Rigid PCB 14 is fixed to shell 12 by fasteners 24 extending throughrespective fastener holes 22 through PCB 14 and engaging fastenerreceptacles 20. Fasteners 24 may be threaded fasteners, and fastenerreceptacles 20 may be internally threaded to mate with a correspondingfastener 24. PCB 14 covers opening 30 and includes electronic circuitry(not shown) for operation of pillow speaker 10. In accordance with afirst aspect of the present invention, shell 12 and PCB 14 cooperatewith one another to form a rigid enclosure assembly for pillow speaker10.

PCB 14 includes an inward surface 38 contacting support surface 32 ofshell 12. As shown in Fig. I, support surface 32 may be recessedrelative to rim surface 34, such that a peripheral edge 40 of PCB 14opposes inner surface 33 of the shell 12. In this arrangement, PCB actsas a rigid member providing structural integrity to the rigid enclosureassembly. For example, if pillow speaker 10 is subjected to an impactforce as may happen if pillow speaker 10 is dropped to the floor,inwardly directed force applied to the outside of shell 12 may beopposed by rigid PCB 14. Applicants have found that a PCB thickness of3.5 mm or greater will provide the rigid enclosure assembly withsuitable structural integrity to withstand forces commonly encounteredduring normal use of the pillow speaker device. However, it will beunderstood that thickness is but one dimension of PCB 14, and PCB's thatare less than 3.5 mm in thickness may be suitable for some applications.The word “rigid,” as used herein to modify PCB, is intended todistinguish from flexible PCBs now on the market, and does not imply aminimum thickness requirement.

In the embodiment of FIG. 1, retainer tab 35 is arranged to engage arecessed portion 37 of an outward surface 36 of PCB 14. Retainer tab 35and recessed portion 37 may be at corresponding longitudinal ends ofshell 12 and PCB 14, respectively, whereby the retainer tab pushes downon the end of the circuit board such that an axial tension force iscreated in fasteners 24 when the fasteners are tightened.

Referring also now to FIGS. 2 and 3, it will be seen that outwardsurface 36 of PCB 14 may include one or more switch traces 54 associatedwith pushbutton control switches enabling a user to enter commands tothe device. Dome layer 16 is arranged adjacent outward surface 36 of PCB14. Dome layer 16 includes a nonconductive sheet 42 and at least oneconductive switch dome 56 attached to the sheet. Sheet 42 may be a thinpolyester layer with adhesive only on its inward surface 44 (FIG. 1) toadhere the sheet to outward surface 36 of PCB 14 as shown in FIG. 3.Each switch dome 56 is applied to adhesive surface 44 of sheet 42 andpositioned to register with a corresponding switch trace 54 on the PCB,wherein the switch dome is operable to close the switch trace byapplying pressure to the switch dome.

Overlay 18 is arranged adjacent dome layer 16 and covers the dome layerto provide switch button embossing, switch graphics, and electricalisolation. Overlay 18 may be a polyester layer having an externalsurface 48 and an internal surface 50 (FIG. 1). Overlay 18 may have anelectrical insulation voltage rating greater than 25 kV, however thisproperty is subject to design choice depending upon the specificapplication. Overlay 18 includes a switch graphic 58 on external surface48 at a location corresponding to an associated switch dome 56 of thedome layer. The switch graphic 58 may indicate a function of the switchbutton to the user, and may include alphanumeric characters or a word.In a commercial embodiment of the invention, the overlay 18 is embossedin the region of each switch graphic 58 and switch dome 56 to provide amore user-friendly tactile push button. The embossing may includeBraille characters to assist blind patients.

As seen in FIG. 4, the internal surface 50 of overlay 18 may include anadhesive portion 50A and a non-adhesive portion 50B. Adhesive portion50A adheres to shell 12 and/or PCB 14, but does not adhere to dome layer16. Dome layer 16 is covered by non-adhesive portion 50B, such thatoverlay 18 and dome layer 16 remain unattached to one another.Accordingly, overlay 18 may be fixed to the outward surface 36 of PCB 14by adhesive at a portion of outward surface 36 not covered by dome layer16. As represented in FIG. 5, adhesive portion 50A may extend beyond aperipheral region of PCB 14 so that it adheres to both the peripheralregion of the PCB and to the rim surface 34 of shell 12.

The present invention extends to a method of making electronic device10. The method generally comprises the steps of providing rigid shell 12defining interior space 15 and opening 30 communicating with theinterior space; providing rigid PCB 14 including electronic circuitryfor operation of the device; and fixing the PCB to the shell such thatthe PCB covers the shell opening, wherein the shell and the PCBcooperate with one another to form a rigid enclosure assembly for theelectronic device. A peripheral edge of the PCB may be arranged tooppose an inner surface of the shell.

According to another aspect of the inventive method, PCB 14 includesoutward surface 36 having switch trace 54 thereon, and the inventivemethod further comprises the steps of providing dome layer 16 includingnonconductive sheet 42 and switch at least one dome 56 attached to thesheet; fixing dome layer 16 to outward surface 36 of PCB 14 such thatthe switch dome is operable to close the switch trace; providing overlay18 overlay including at least one switch graphic 58; and fixing overlay18 to at least one of the shell 12 and the outward surface 36 of PCB 14such that the switch graphic 58 is at a location corresponding to theswitch dome 56, wherein the overlay 18 is unattached to dome layer 16.The dome layer 16 and the overlay 18 may be fixed to the outward surface36 of PCB 14 by adhesive at different portions of the outward surface36. Overlay 18 may also be fixed to shell 12 by adhesive. The stepsmentioned in this paragraph also represent an improved method of makingelectronic device 10 for a health care setting, independently of thesteps for constructing the rigid enclosure assembly described in theimmediately preceding paragraph.

The present invention eliminates the need for a second rigid piece toform an enclosure assembly by using the PCB for structural function inaddition to electronic function.

Moreover, the use of a dome layer and an overlay that are unattached toone another reduces cost, improves tactile feel of the buttons, andfacilitates servicing of the device. Cost is reduced due to the factthat the dome layer 16 carries only the metal switch domes 56, wherebythe dome layer may be configured for use with a large number ofcorresponding overlays 18. This reduces the number of different partnumbers for manufacturing specifications. Tactile feel is improvedbecause the user feels the entire tactile feel of the metal dome 56itself, which was not the case with prior art switch membranes where theoverlay and switch dome were physically coupled to one another.Serviceability is improved because only the overlay 18 needs to bediscarded and replaced when the device is opened up, and the dome layer16 including costly metal domes 56 can remain and be reused.

With regard to serviceability, the present invention is further embodiedby an improved method for servicing an electronic device of a typecomprising a PCB including a switch trace, a switch dome operable toclose the switch trace, and an overlay including a switch graphic at alocation corresponding to the switch dome. The servicing method of thepresent invention comprises the steps of removing the overlay 18 fromthe device 10 without removing the switch dome 56 from the device 10;performing a service operation; and fixing a replacement overlaydifferent from the removed overlay on the device overtop the originalswitch dome 56.

Modifications and other embodiments of the inventions set forth hereinwill be apparent to one skilled in the art to which these inventionspertain in light of teachings presented in the present specification.Therefore, the inventions are not to be limited to the specificembodiments disclosed, and modifications and other embodiments areintended to be included within the scope of the appended claims.

PARTS LIST

-   10 Electronic device (pillow speaker)-   12 Shell-   12A First shell portion-   12B Second shell portion-   13 Ultrasonic weld seam-   14 Printed circuit board (PCB)-   15 Interior space of shell-   16 Dome layer-   18 Overlay-   20 Fastener receptacles-   22 Fastener holes through PCB-   24 Fasteners-   26 Cord passageway-   28 Speaker mount-   30 Shell opening-   32 Support surface for PCB-   33 Inner surface of shell-   34 Rim surface of shell-   35 Retainer tab-   36 Outward surface of PCB-   36A Portion of outward surface of PCB not covered by dome layer-   38 Inward surface of PCB-   40 Peripheral edge of PCB-   42 Nonconductive sheet of dome layer-   44 Adhesive surface of nonconductive sheet-   46 Cut-out regions of nonconductive sheet-   48 External surface of overlay-   50 Internal surface of overlay-   50A Adhesive portion of internal surface of overlay-   50B Non-adhesive portion of internal surface of overlay-   54 Switch traces on outward surface of PCB-   56 Switch domes of dome layer-   58 Switch graphics of overlay

1.-9. (canceled)
 10. A method of making an electronic device for use ina health care setting, the method comprising the steps of: providing arigid shell defining an interior space and an opening communicating withthe interior space; providing a rigid printed circuit board, the printedcircuit board including electronic circuitry for operation of thedevice; and fixing the printed circuit board to the shell such that theprinted circuit board covers the opening, wherein the shell and theprinted circuit board cooperate with one another to form a rigidenclosure assembly for the electronic device.
 11. The method accordingto claim 10, wherein a peripheral edge of the printed circuit boardopposes an inner surface of the shell.
 12. The method according to claim10, wherein the printed circuit board includes an outward surface havinga switch trace thereon, and the method further comprises the steps of:providing a dome layer, the dome layer including a nonconductive sheetand a switch dome attached to the sheet; fixing the dome layer to theoutward surface of the printed circuit board such that the switch domeis operable to close the switch trace; providing an overlay, the overlayincluding a switch graphic; and fixing the overlay to at least one ofthe shell and the outward surface of the printed circuit board such thatthe switch graphic is at a location corresponding to the switch dome,wherein the overlay is unattached to the dome layer.
 13. The methodaccording to claim 12, wherein the dome layer and the overlay are fixedto the outward surface of the printed circuit board by adhesive atdifferent portions of the outward surface.
 14. The method according toclaim 13, wherein the overlay is fixed to the shell by adhesive. 15.-18.(canceled)
 19. A method of making an electronic device for use in ahealth care setting, the device comprising a printed circuit board fixedto a housing shell, the printed circuit board including an outwardsurface having a switch trace thereon, wherein the improvement comprisesthe steps of: providing a dome layer, the dome layer including anonconductive sheet and a switch dome attached to the sheet, fixing thedome layer to the outward surface of the printed circuit board such thatthe switch dome is operable to close the switch trace; providing anoverlay, the overlay including a switch graphic; and fixing the overlayto at least one of the housing shell and the outward surface of theprinted circuit board such that the switch graphic is at a locationcorresponding to the switch dome, wherein the overlay is unattached tothe dome layer.
 20. The method according to claim 19, wherein the domelayer and the overlay are fixed to the outward surface of the printedcircuit board by adhesive at different portions of the outward surface.21. The method according to claim 20, wherein the overlay is fixed tothe housing shell by adhesive.
 22. A method of servicing an electronicdevice, the device comprising a printed circuit board including a switchtrace, a switch dome operable to close the switch trace, and an overlayincluding a switch graphic at a location corresponding to the switchdome, the method comprising the steps of: removing the overlay from thedevice without removing the switch dome from the device; performing aservice operation; and fixing a replacement overlay different from theremoved overlay on the device overtop the switch dome.